VMware has released a hotfix for vSphere Data Protection (VDP) to change a hard-coded SSH key that could allow remote attackers to gain root access to the virtual appliance.

VDP is a disk-based backup and recovery product that runs as an open virtual appliance (OVA). It integrates with the VMware vCenter Server and provides centralized management of backup jobs for up to 100 virtual machines.

According to a VMware support article, the vSphere Data Protection (VDP) appliance contains a static SSH private key with a known password. This key allows interoperability with EMC Avamar, a deduplication backup and recovery software solution, and is pre-configured on the VDP as an AuthorizedKey.

"An attacker with access to the internal network, may abuse this to access the appliance with root privileges and further to perform a complete compromise," VMware said.

The company rates this vulnerability as critical and developed a hotfix that can be copied and executed on the appliance to change the default SSH keys and set a new password.

Developing devices with hard-coded access credentials that users can't change is a serious security weakness. Unfortunately, this was common practice in the past and vendors have been trying to clean up such mistakes from their devices for the past few years.

On Tuesday, VMware also fixed a stored cross-site scripting vulnerability in its vSphere Hypervisor (ESXi) product. The flaw is rated as important.

"The issue can be introduced by an attacker that has permission to manage virtual machines through ESXi Host Client or by tricking the vSphere administrator to import a specially crafted VM," the company said in an advisory. "The issue may be triggered on the system from where ESXi Host Client is used to manage the specially crafted VM."

VMware released security fixes for ESXi 5.5 and 6.0 to fix this flaw and advises users not to import VMs from untrusted sources.